Thomas burciiill



Ne1) T. BURGHILL.

SCREW SEVERING ATTACHMENT FOR SCREW DRIVING MACHINES. No. 569,744. Patented out. 20,1896.

l 66. i im f m UNITED STATES PATENT FFlCEE THOMAS BURCI'IILL, OF CINCINNATI, OHIO, ASSIGNOR TO TIIE EMERSON d: FISHER COMPANY, OF SAME PLACE.

SCREW-SEVERING ATTACHMENT FOR SCREW-DRIVING MACHINES.

SPECIFICATION forming part of Letters Patent No. 569,744, dated October 2(1), 1896.

Application Bled April 6, 1896. Serial No. 586,295. (No model.)

.To all 'uf/tom t mlm] (sorteer/1,:

Be it known that I, THOMAS BURCHILL, a citizen of the United States, residing at Cincinnati, in the county of Hamilton and State 5 of Ohio, have invented certain new and useful Improvements in Serew-Severing Attachments for Screw-Driving Machines, of which the following is a full, clear, and exact description, reference bein g had to the aecom- 1o panying drawings, forming part of this speciiieation.

My improvements relate to devices for severin g the heads of screws, after they have been driven to place in woodwork and the like,

where for any purpose the removal of the heads oi the screws is desired, and my invention has particular relation to such attachments when used in connection with screwdriving machines as employed by vehiclewheel mamifacturers.

In the manufacture of vehicle-wheels it is customary to drive screws into the telly on each side of the spokes to hold the spoke and prevent the felly from splitting. These screws 2 5 have often been driven by machines provided with a vertically-m ovable and rapidlyrevolving mandrel arranged to hold the screw by its head and drive it into the wood. IIeretofore after the screws have been thus driven it has 3o been customary then to remove the screwheads one at a time with a pair of hand-pincers. This is necessarily quite a tedious undertaking, involving considerable time and labor, which it is the purpose of my invention to dispense with 5 and the invention consists of certain devices, to be hereinafter particu- 'larly pointed out and claimed, arranged to be attached to the screw-drivin g mechanism, whereby the moment the screw is driven to place the screw-heads will be automatically severed 'from their stems.

In the drawings, Figure l is a central vertical section of my attachment, showing the toggle-nippers in i'ront elevation. Fig. 2 is a side elevation of the same. Fig. 3 is a detail view, in central vertical section, wi th the nippers in position to sever the screw-head.

A is the verticaliy-movablc mandrel ot' the screw-driving machine and rotated at any dcsired speed by the power-driven shaft I3 and beveled gear O, which meshes with the beveled gear D, mounted on and keyed to the mandrel, the shaft I3 and mandrel A being supported in the sleeves E Il", secured to the frame of the machine. i

Upon the lower end of the mandrel is tightly coupled or otherwise secured-the sleeve F. This sleeve carries in a central recess therein the screw-holder G, which holder is recessed and grooved at its lower end to conform to 6o and hold the head of the screw. The screwholder G passes loosely through the sleeve F and up into a recess ce in the mandrel, while a coiled spring b bears between the mandrel and an adjustable nut e on the screw-holder, thus normally keeping the holder extended, but allowing it to be pressed back against the spring-pressure, the recess d in the sleeve being enlarged to allow play for the nut and to furnish an abutment for the nut to prevent 7o the holder from dropping from the attachment.

e is a collar or nut mounted on and adjustable on the outer end of the screw-holder, by the adjustment of which the distance the screw-holder can be vpressed upward is regnlated.

II II are a pair of nipping or cutting jaws pivoted at ff to the sleeve F and at g g to the toggle-bars 7i 7l. The toggles 71. 7L are pivoted 8o to the collar K, which is mounted loosely on the mandrel, the upper portion of the collar being formed with a groove to receive the split ring It, to which are secured the outer ends of the hifureated yoke L, the lever-arm 8 5 M of whichis coupled by connecting-rod m. with hand-lever n and with a foot-treadle, (not shown,) so that the lever M can be shifted either by hand or toot, as may be most convenient. 9o

The lever M is pivoted in the slot p to the frame of the machine, so that the mandrel can be moved vertically thereby. On the upper portion of the mandrel is adjustably secu red by set-screws or otherwise the collar N, o5 which limits the downward play of the mandrel and screw-driver, while a spring i', attached to levorM and the frame, holds up the operating parts, until brought into action, with the collar Ii against the sleeve E.

Before the screw is inserted in the holder the cutting-jaws II II are held apart by com- IOOV jaws to come in contact with the screw immediately under the head or at such a point on the stem of the screw as it maybe desired to cut oit same, the portion of the screw to be cut ott being regulated bythe distance the nut e is adjusted from the base of the sleeve I?, inasmuch as the position of the cuttingjaws is fixed with relation to the sleeve, as they are pivoted t-hereto.

In screw-driving machines it is usual to have a table upon which the work is placed, and as the table is in a fixed position itis also necessary to adjust the distance from the end of the screw-holder to the wood for the varying thickness of wheel-fellies, so that the oper-- ator shall alwayshave room between the wood and driver to insert the screw inthe holder. This adjustment is obtained by the adjusting of the nut c so that the springbinay advance the screw-holder a greater or less extent, as required. Then the distance the screw is to be driven into the wood (usually about the length of the screw) is determined by the adjustment of the collar N from the gearwheel D,

In order that the cutting edges of the jaws II II may be kept sharp, I prefer to insert a hardened-steel cutting-blade Ain the end of the jaws, which can he removed for sharpening.

The operation of the device will be evident from the description already given.

Having made the 'necessary adjustments for the work required, the mandrel and attachment are set in rapid rotation and the operator inserts the screw in the holder, pressing back the same and allowing the cutting-jaws to come together around the screw. The lever M is then depressed, bringing down the mandrel and driving the screw, the resistance of the screw against the cutting-jaws allowing the mandrel to descend rather than the jaws to cut. As soon as the screw is driven in and the collar N comes in contact with the gear D the mandrel necessarily stops in its descent, aud the downpressure on the lever M now is at once transferred to the toggles, driving the cutting-jaws through the screw and at once severing the head. In this way all of the time and labor heretofore spent in outVL ting off the heads of the screws by hand are entirely saved, as the moment the screw is driven to place the head is removed by the cutting-jaws.

Having thus described my invention, what I claim, and desire to secure by Letters Patent of the United States, is-

1. In a screw-severing attachment,the combination, with a screw-driving mandrel, of cutting-jaws pivoted thereto, toggle-bars pivoted to said jaws, and means for operating same, whereby the screw may be severed at the completion of the mandrel stroke, substantially as shown and described.

2. In a screw-severing attachment, the conibination, with a screw-driving mandrel, of cutting-jaws pivoted thereto, collar mounted and sliding on said mandrel with toggles connecting said collar and cutting-jaws, and lever for operating said mandrel coupled to said collar, whereby the screw may be severed at the completion of the mandrel stroke, sub` stantially as shown and described.

In a screw-severingattachment, the combination, with a screw-driving mandrel, of cutting-jaws pivot-ed thereto, collar mounted and sliding on said mandrel with toggles connecting said collar and cutting-jaws, lever for operating said mandrel coupled to said collar, movable screw-holder adjustably secured to said mandrel, with spring to normally hold said screw-holder extended, to separate the cutting-jaws and allow for the insertion of the screw, substantially as shown and described.

4. In a screw-severing attachment, the oombination, with a screw-driving mandrel carrying a fixed sleeve at its outer end, with recesses formed therein, and screw-holder movably mounted in said recess, spring and stopnut within said recess, to keep said holder extended, cutting-jaws pivoted to said sleeve, with means for operating same, and an adjustable nut on the outer end of said screwholder, whereby the amount of cut oi the cutting-jaws may be regulated, substantially as shown and described.

THOMAS BUROHILL.

`\Vitnesses:

GEORGE IIEIDMAN, HARVEY EDWARDS.

ICO 

